The invention relates to a device for metering a granular material, such as a free-flowing microgranulate, which is applied in exactly metered quantities, it being necessary for the user to be protected as far as possible against contact with the granular material.
Until now, products in liquid form have predominantly been used as soil disinfectants for treating overhead-line masts in the open air. Dispensing liquid soil disinfectants against nematodes, soil-borne diseases, soil insects and germinating weeds is subject to numerous disadvantages. When liquid products are dispensed by means of spray devices, plumes of spray mist are produced, even when there is a moderately severe wind, and their inspiration can be extremely hazardous for the user dispensing the soil disinfectant. In the case of soil disinfectants to be dispensed in liquid form, there is additionally the residual quantity problem, since the packaging containers containing the residual quantities are often extremely difficult to empty completely. In order nevertheless to achieve the most complete emptying of he containers containing the soil disinfectant, the products are transferred, which entails not inconsiderable risks for the person handling the disinfectant as a result of its running out.
Apart from the use of liquid soil disinfectants or pesticides, structures made of timber, such as overhead-line masts, foot bridges or bridge superstructures may necessitate a treatment against fungicidal attack, it being necessary for the pesticide to be introduced into the interior of the timber structure, be it an overhead-line mast, a pier or more of the like. For this purpose, holes are bored into the timber components to be treated, into which holes a free-flowing, fine-grained granulate has to be introduced in an exactly metered manner.
In view of the technical problem indicated, the invention is based on the object of providing a metering device which is largely shielded against the environment and permits the granular material to be dispensed directly without the person handling the metering device being exposed directly to the material to be dispensed.
According to the invention, the object is achieved by a metering device for dispensing a free-flowing, fine-grained granular material, which device comprises a housing which holds said material, it being possible for the metering device to be connected to a packaging container in which the fine-grained material is stored and for the housing to be closed by means of two closures, which can be moved alternately from an open position into a closed position.
The solution proposed by the invention permits any contact to be avoided between the user of the metering device and the granular material to be dispensed. The ability of the housing to be connected via two closures to a packaging container that stores the granular material, means that said container can be emptied in such a way that no disposal of residual quantities arises, and it is not necessary to transfer a material which is extremely damaging to the health of the user, such as a timber treatment agent or a soil disinfectant.
In a further refinement of the idea on which the invention is based, the closures are particularly advantageously accommodated in the end regions of the housing. The end regions of the housing can be, for example, ends which are produced from plastics and which each have an opening which can be closed and opened by a pivotable flap in each case let into the plastic end of the housing. The closures can be connected to each other both in a form-fitting manner and with a force fit; the respective actuation of a closure is carried out in a manner coordinated with the actuation of the respective other closure. The housing, which holds the supply of free-flowing, fine-grained material, is advantageously fabricated from transparent material and can consist either of glass or of an impact-resistant and fracture-resistant plastic material. Transparent material permits simple visual inspection of the supply of material still located in the housing.
In order to limit the quantity of the respective material to be dispensed which can be held in the housing, disk-like elements can be inserted into said housing. These can be provided in the end regions of the housing, or else designed as funnel-like, annular elements and promote the discharge of material through the openings accommodating the closures in the plastic ends. In order to store a larger quantity of material within the housing, an existing housing can simply be replaced by a lengthened housing which can hold a larger supply of material. In order to move the closures integrated into the end regions of the housing, an actuating element is accommodated in one of the end regions of the housing and accommodates a rotary element, whose recesses engage in cams. As a result, the cams, which are fixed to drivers, engage in the rotary element, as a result of which the cams have a rotation impressed on them, which pivots the closures via transmission elements which extend parallel to the axis of the housing.
Bores which open into outlet connecting pieces which are integrally molded at the end regions are advantageously provided in the end regions, fabricated from plastic, for example. This permits the simple input of material into the housing which stores the granular material, and in addition the free-flowing, fine-grained material can easily be inserted into correspondingly inclined bores provided in timber structures.
For the easier handling of the free-flowing materials to be dispensed, in the central position of the actuating element, both closures are in a closed position and are sealed off with respect to the two outlet connection pieces, so that the supply of material held in the housing is sealed off from the outside. When the actuating element is pivoted from its central position, in the first deflected position of the actuating element, the first closure is closed and the second closure is open, pivoting the actuating element back into its central position allows both closures to be moved into their respectively closed position; pivoting the actuating element into the second deflected position, beyond the central position, opens the first closure and closes the second closure with respect to the connecting piece.
The discharge, the storage and the refilling of the housing of the metering device according to the invention are carried out via an actuating element which can be pivoted into three positions and which is very simple to operate. Accommodated on the housing which stores the free-flowing granulate is a handle, with which the housing can be handled; located beside the handle is the grip area of the actuating element, which may be operated without releasing the handle and permits the metering device to be handled even by those persons who are inexperienced in handling the metering device.